Is there a "how to.." for crank measurement, and bearing verification? |
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Is there a "how to.." for crank measurement, and bearing verification? |
malcolm2 |
Dec 16 2019, 11:07 PM
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#1
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Advanced Member Group: Members Posts: 2,747 Joined: 31-May 11 From: Nashville Member No.: 13,139 Region Association: South East States |
I am gonna make a 2 liter from my 1.8. So I have a refreshed 71mm crank that I have been told has been ground to -0.010.
I measured as best as I can with a digital mic and got about 59.66 on the mains and 49.65 on the rod journals. Where can I find the STD specs and ranges ? were they 60 and 50, respectively? Since I know nothing about this crank, how can I verify the 71 mm measurement? |
Mark Henry |
Dec 21 2019, 03:24 PM
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#2
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that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
Sounds like a lot. If you're right about #4 you'll be lucky to get it ground at .010 under.
You need to send it to a crank shop, once done they will tell you (tag) what sizes you need. I never use plastigage, nether does Raby IIRC. Your rods should at least have the big ends done. Honestly if you're not doing that then it's a recipe for disaster. |
malcolm2 |
Jan 20 2020, 08:59 AM
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#3
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Advanced Member Group: Members Posts: 2,747 Joined: 31-May 11 From: Nashville Member No.: 13,139 Region Association: South East States |
Your rods should at least have the big ends done. Honestly if you're not doing that then it's a recipe for disaster. OK, I am back on the engine.... at least research. So what do you mean, "have the big ends done"? I found rod bearings at CIP1.com that are listed only as STD or -0.010, etc... $33 for a set. I assume that the "under" listing is to note the machining on the crank. Is this what I should look for, simply -0.010? If the rods were "done" would that mean that they have been trued up? Ground or polished or just re-bearing-ed? Blizzard has provided me a set of 2.0 liter rods that he has balanced. So I have something to work with here. The link provided by superhawk above, only deals with 1.7 and 1.8 engines.... at least that I can find. 251 pages on the engine, so I could have missed it. So I am still looking to find the factory spec on the "big end" as a starting place and to determine if Mike's rods have been "done". So question 1: how do you "DO" the rods? question 2: What Rod bearings to get, how are they listed? Thanks |
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